Newman's cookies, on the right, have deep chocolate cookie wafers and a creamy filling. Surprisingly tasty. According to America's Test Kitchen TV show, Oreo filling is sweetened solid hydrogenated oil (i.e., Crisco and sugar).
And try the Fig Newmans. I think they are tastier (maybe healthier) than the standard Fig bar brand. If you try Fig Newmans, get the package labeled Low Fat (the Fat Free tastes dry and not tender and chewy).